U.S. Pat. No. 5,292,979 describes a process for the conversion of ethylene into light alpha-olefins comprising contacting ethylene with at least one catalyst obtained by the reaction of a preformed mixture of alkyl zirconate and ether, in an ether/zirconate molar ration of 0.5:1 to 10:1, with at least one aluminium compound of general formula AlRnX3-n, in which R is a hydrocarbyl radical, X is a chlorine or bromine atom and n is 1-2.
U.S. Pat. No. 5,157,190 describes a process for making higher alpha-olefins from ethylene by chain growth comprising the steps of feeding ethylene and an alkyl aluminium compound to a reaction zone maintained under chain growth conditions to produce tri-alkyl aluminium compounds, feeding at least a part of said tri-alkyl aluminium compounds and butene as reactants to a displacement zone maintained under displacement conditions to form a butene displacement product comprising mainly tri-butyl aluminium, ethylene and alpha-olefins and conveying the tri-butyl aluminium to a chain growth zone fed with additional ethylene.
EP257232 describes a process for oligomerising ethylene to normal alpha-olefins and recovering said olefins from the reaction product, which comprises reaction ethylene in a methanol-water mixture containing 0.5-20 wt % water under oligomerisation conditions in contact with a nickel ylide catalyst.
U.S. Pat. No. 4,487,847 describes a novel ethylene dimerisation catalyst to make 1-butene. Said catalyst consists of a nickel compound, a phosphine compound, and an acidic compound in an effective solvent at a temperature from about 0° C. to about 200° C.
EP135441 describes an improved process for converting ethylene to 1-butene, wherein ethylene is contacted with a catalyst obtained by reacting an alkyl titanate with an alkyl aluminium compound, characterised in that said catalyst results from reacting a preformed mixture of alkyl titanate and ether, in a molar ratio ether/titanate form 0.5:1 to 10:1, with an aluminium compound of formula AlR3 or AlR2H, wherein each R is a hydrocarbyl radical.
U.S. Pat. No. 5,221,775 describes an ethylene dimerisation process wherein ethylene is contacted with an organonickel(0) compound and a phosphine compound in a fluorinated alcohol solvent to produce a precursor reaction mixture, followed by contacting ethylene with the precursor reaction mixture and a fluorinated organoacid to produce a product reaction mixture comprising a C4 fraction of predominantly 2-butenes.
U.S. Pat. No. 5,672,802 teaches a process for the preparation of an alpha-olefin product having a narrow molecular weight range which comprises metathesizing an internal olefin under non-equilibrium conditions and thereby producing a lower boiling internal olefin product which is removed as formed, and a high boiling mid-chain internal olefin product, thereafter contacting and reaction the high boiling mid-chain internal olefin product with ethylene to produce an alpha-olefin product having a narrow molecular weight range.
EP803490 describes a process for the conversion of ethylene to but-1-ene, wherein, in a reaction enclosure, the ethylene is brought into contact with a solution of a catalyst resulting from the interaction of at least one alkyl titanate with at least one aluminium compound of the formula AlR3 or AlR2H, each of the residues R being a hydrocarbyl radical, the process being characterised in that it takes place in the presence of at least one additive selected from the group formed by quaternary ammonium salts.
In US 2001/0023281 a process to produce 1-hexene is described wherein a catalytic composition is obtained by mixing at least one chromium compound with at least one aryloxy compound of an element M selected from the group formed by magnesium, calcium, strontium and barium, with general formula M(RO)2-nXn where RO is an aryloxy radical containing 6 to 80 carbon atoms, X is a halogen or a hydrocarbyl radical containing 1 to 30 carbon atoms and n is a whole number that can take values of 0 to 2, and with at least one aluminium compound selected from hydrocarbylaluminum compounds (tris(hydrocarbyl)-aluminum, chlorinated or brominated hydrocarbylaluminum compounds) and aluminoxanes. The catalytic composition can be used in an ethylene oligomerisation process, in particular to produce 1-hexene.
U.S. Pat. No. 5,198,563 describes a catalyst for producing in particular 1-hexene whereas novel chromium-containing compounds, such as, for example, chromium pyrrolides, are prepared by forming a mixture of a chromium salt, a metal amide, and an electron pair donor solvent, such as, for example, an ether. These novel chromium-containing, or chromium pyrrolide, compounds can be used either unsupported or supported on an inorganic oxide support to trimerize and/or polymerize olefins.
In all the above prior arts ethylene is not originating from ethanol.
In U.S. Pat. No. 7,223,895 an ethane or other hydrocarbon feedstock is steam cracked to produce an ethylene stream which is processed in an ethylene plant recovery section to separate an ethane recycle and a polymer grade or chemical grade ethylene product stream. A portion of the ethylene product stream may then be reacted by dimerization to produce a butene stream. These formed butenes and/or butenes recovered from other sources and another portion of the ethylene product stream are reacted by metathesis to produce a propylene stream which is deethanized and separated from heavier hydrocarbons to produce the propylene product. The butene product stream may also be deethanized and is separated from heavier hydrocarbons. The overhead from the metathesis section deethanizer may be recycled to the ethylene plant recovery section. The reflux for the metathesis section deethanizer may be generated from the overhead or may be a portion of the ethylene product stream. In said prior art ethylene is not originating from ethanol and has to be purified by a selective hydrogenation to remove acetylene.
US20070112236 describes an integrated method that comprises an ethane thermal cracking operation to form at least ethylene, coupled with dimerization and metathesis operations, the dimerization operation forming butene for the metathesis operation, and the metathesis operation forming additional amounts of propylene. In said prior art ethylene is not originating from ethanol and has to be purified by a selective hydrogenation to remove acetylene.
US20070203384 describes a process for producing light olefins from an oxygenate-containing feedstock, said process comprising:
contacting the oxygenate-containing feedstock in an oxygenate conversion reactor with an oxygenate conversion catalyst and at reaction conditions effective to convert the oxygenate-containing feedstock to an oxygenate conversion effluent stream comprising light olefins and C4+ hydrocarbons, wherein the light olefins comprise ethylene and the C4+ hydrocarbons comprise a quantity of butenes including a quantity of 1-butenes; treating the oxygenate conversion effluent stream and forming a first process stream comprising at least a portion of the quantity of butenes including 1-butenes from the oxygenate conversion effluent stream;
isomerizing at least a portion of the quantity of 1-butenes of the first process stream to form an isomerized stream comprising a quantity of 2-butenes;
contacting at least a portion of the quantity of 2-butenes of the isomerized stream with ethylene in a metathesis zone at effective conditions to produce a metathesis effluent stream comprising propylene; and
recovering propylene from the metathesis effluent stream. In said prior art ethylene is not originating from ethanol.
WO2007083241 relates to a production method for propylene characterized in that ethanol is converted into propylene by continuously reacting ethanol on a catalyst. More precisely the ethanol is converted into the propylene by:
forming ethylene through a dehydration reaction between the catalyst and the ethanol;
forming a butyl cation through a dimerization reaction between the ethylene formed and an ethyl cation obtained from the catalyst;
forming a butene from the butyl cation;
forming a carbocation through a trimerization reaction between the butene and the ethyl cation; and
forming propylene through a cleavage reaction of the carbocation.
The catalysts for the dehydration, dimerisation, trimerisation and cleavage reaction is a solid acid. There are no examples describing clearly an ethanol feedstock, a catalyst, a reactor, operating conditions and the composition of the effluent deemed to comprise propylene.
EP1953129 A1 (=WO 2007-055361) explains that ethanol obtained from ordinary biomass resources contains many impurities other than water and these impurities themselves or their decomposition products contaminate ethylene when the ethylene is produced by a dehydration reaction, whereby the activity of metathesis catalyst is adversely affected. According to EP1953129 A1 a method for producing propylene is characterized in that the ethanol obtained from biomass is converted to ethylene by a dehydration reaction, the ethylene is separated from the generated water, the separated ethylene is purified by adsorption in an adsorption tower filled with an adsorbent, and then a metathesis reaction is carried out along with a raw material containing n-butene. Optionally said butene is made by dimerization of ethylene obtained by dehydration of ethanol. As a consequence propylene having biomass-derived carbon and reduced-environmental burden can be produced without lowering the catalysis activity.